Catheters or probes are increasingly used in invasive medicine. Such catheters or probes enable body cavities or the vascular system to be analyzed or treated, e.g. intravascular ultrasonic probes being used in diagnostic medicine. While classical angiography only enables changes in longitudinal section and in particular stenoses in blood vessels to be identified, information about the condition of vascular walls can be successfully obtained with such intravascular ultrasonic catheters. In particular, information about calcification, lipoid or fibrotic structures of vascular walls can be obtained with such intravascular ultrasonic catheters, which information in particular serves as a check following interventions, such as, e.g., a stent implantation, to determine whether there are vascular wall injuries or not. Besides intravascular ultrasonic catheters, in which at least one piezoelectric crystal is arranged at the probe head to obtain an image, probes have already been used for treatment, such as, e.g., for intravascular radiation. When a so-called imaging catheter is equipped with only one crystal to obtain an image of the internal wall of a vessel, it is required for completely imaging the vascular wall to rotate this catheter about its axis during withdrawal, so that the image can be obtained as a spirally developed view of the vascular wall. Besides a regulated or constant number of revolutions, a regulated or constant speed during withdrawal of the catheter is a prerequisite. Besides such rotatably driven imaging catheters, there are also known structures having a plurality of crystals which are scanned in a corresponding phase. In such so-called "phased array" catheters, the rotation of the catheter can be omitted. However, an unavoidable prerequisite for a reproducible evaluation of the images is again a defined, in particular constant driving speed during withdrawal of the catheter. For intravascular radiations, too, a uniform feed is essential for the exact dosage. Moreover, during the uniform feed a concentration or ion gradient can be determined in vessels and organs.
The hitherto known devices for withdrawing catheters are relatively heavy and large. In rotating intravascular ultrasonic catheters the heavy motor required for rotational drive is then placed in a corresponding holding device and moved in the longitudinal direction of the catheter together with the axially movable part of the catheter. At the operating table there is hardly any room for such large and heavy devices, so that their handling is relatively laborious. Moreover, such devices usually cannot be sterilized without additional measures, and it is therefore necessary to use them in a corresponding sterile package, which further complicates their handling. Moreover, these known heavy and large devices are very expensive and usually can only be used in connection with a specific drive, e.g. for an intravascular ultrasonic catheter.
NL 10 00 685 C2 shows and describes a device for the controlled movement of a catheter, which comprises a resilient frame open on one side, in which a driving device connected with one end of the frame, such as, e.g., an arm or a pinion, cooperates with the catheter passed into openings in the frame. The frame is compressed manually, with the catheter being moved through the driving device. An adjusting screw enables the compression to be limited and thus a defined stroke and a defined path of movement of the catheter to be adjusted. Additionally, electric contacts are provided at the frame, with which a signal corresponding to the movement of the catheter can be produced during the compression of the frame.
U.S. Pat. No. 4,233,991 A shows and describes a device for withdrawing a urethral catheter, which comprises withdrawing the catheter through a spindle drive connected to a motor. The catheter is connected to the spindle drive via clamping devices.